Ball point writing implement



A ril 18, 11950 1. CHESLER 5 5 I BALL POINT WRITING IMPLEMENT Filed Feb. 14, 1945 "WI 1 25 W :5; 14 t 23 \&

14 W; 20 26 SE '22 2a INVENTOR [sz'dofl LVzem m BY AM my ATTORNEYS Patented Apr. 1 8 195 6 BALL POINT WRITING IMPLEMENT Isidor Chesler, Oceanport, N. .L, assignor to Eagle Pencil Company, a corporation of Delaware Application February 14, 1945, Serial No. 577,773

3 Claims. 1

The present invention relates to writing implements more particularly of the type that may properly be designated as ink pencils.

It is among the objects of the invention to provide an implement of the above type of simple, compact and relatively inexpensive construction made up entirely of rigid elements, readily machined or molded at small cost, and easily assembled and which is correspondingly rugged,

which affords an almost indefinite supply of ink and does not require refilling for a period of years, which will unfailingly make an ink line that is substantially smudge-proof and requires no blotting and this without the slightest danger of flooding, regardless of the temperature, humidity or atmospheric pressure of the environment.

According to the invention, the supply of ink is confined in an elongated capillary passageway conformed in a core plugging the barrel and preferably by appropriate groove conformation on the face of the plug forming in cooperation with the barrel wall the desired capillary void which desirably may be in helical form. The ink being made to fill the capillary passageway in the absence of entrapped air is propelled toward the writing point under atmospheric pressure through event in the barrel. The point is movable, preferably of the ball type and is normally maintained against its outer seat by theweight of the column of ink in the passageway thereby to preclude leakage.

In the accompanyin drawings in which is shown one of various possible embodiments of the several features of the invention,

Fig. 1 is a view in longitudinal cross-section through the implement,

Fig. 2 is a transverse sectional view on an enlarged scale showing the writing tip construction, and

Fig. 3 is a view in transverse cross-section taken on line 3-3 of Fig. 2 with the ball removed.

Referring now to the drawings, the barrel ll! of the implement is cylindrical throughout its main length but desirably tapers or is generally frusto-conical as at l l at its forward end.

Plugged within the barrel is a core l2 which may be of. metal, plastic 01' the like, machined or molded and which snugly fits the cylindrical bore and has a reduced conical end [3 snugly fitting the conical writing end H of the barrel. This core affords one or more capillary conformations for accommodating the ink in one or more columns. While the ink may thus be accommodated in bores through the core, it is preferable to accommodate it in one or more elongated capillary conformations defined between the bore of the barrel and the surface of said plug. Desirably the conformation is a helical groove 14 in the wall of the core, of uniform depth, in the order of .10 inch and of width desirably somewhat less than its depth as shown. The root diameter of the groove is desirably constant as shown, the depth of the groove correspondingly decreasing as shown, at the conical end. The groove does not extend clear to the upper end of the core l2 but the core has a smooth uninterrupted cylindrical upper end I5, with an axial bore l6 therein of relatively large diameter, which communicates with the groove M through a, radial bore or port I! of very small diameter.

The lower or writing point end of the core also has an axial bore l8 therein, which communicates through a radial bore l9 with the lower part of the helical groove 14 which groove terminates before the lower end of the core as at l4 so that the conical end of the core, below the end M of the groove, which coacts with the inner wall of the barrel serves as a stopper. The threaded nipple 24 of the tip is screwed into the corre spondingly tapped socket 25 in the forward end of the core l2, with the shoulder 26 of the tip seated against the forward open end of the barrel, thereby causing the conical end of the core tightly to be seated in the conical front ll, of the barrel as shown.

The implement has a tip 2!! which accommodates the movable writing point preferably in the form of a ball 2 I. The tip has a longitudinai bore 22 communicating through a reduced axial bore 23 directly with the surface of the ball 2| mounted in the forward end of said tip. The backstop 21 for the ball is thus an integral part for the tip. The ball is held against said backstop by the inturned rim 28 of the tip. Desirably the backstop is roughened as, for instance, by milling as at 29 and so the fiow of ink can take place to the annular chamber 30 about the inner end of the ball.

The ink groove [4 is vented to atmosphere at its upper end through the bore 16 and through the preferably axially disposed vent hole 3| in the cap plug 32 threaded at 33 into the upper end of the barrel.

The ink maintained in the capillary passage 14 preferably extends from the ball 2| to a point 34 substantially below the upper end of groove l4. Therefore no ink will escape under expansion with rise in temperature. Since the helical passageway M of the substantial volumetriccapacity shown might not afford adequate capil-- larity, were the ink of the liquid or free flow type,

out ahead of it as it passes into and fills the capillary passageway.

The operation of the implement, though probably clear from the foregoing, will be briefly set forth. The weight of the column of pasty ink devoid of entrapped air in the capillary vessel, chamber or passageway, will press against the ball writing point 2!, which under such pressure is normally urged against the inturned lip 28, the ball acting as a valve to preclude leakage. In writing, the ball 2] picks up such pasty ink chiefly from axial bore 23 and also from the cavity 30. The pasty inlndue to the weight thereofiis 'alwaysreliably brought in contact with the ball at bore 23.

Theball' writing point delivers only sufficient ink to make a thin smudge-proof line that requires no blotting.

As-previously noted, rise of temperature will not cause flooding, because the pasty ink will simply expand into the upper end of the helical .groove. Under :subatmospheric pressure, say in :airplane travel, the pen will feed somewhat less :freely and unlike ordinary fountain pens, it will not-flood.

The radial bore i? being as shown of small diameter, (.025 o .036 inch) much smaller than that of a 'vent hole such as hole 3!, acts as a dashpot or air cushion which releases the air slowly to prevent the pasty ink from surging forward past the upper end of the core i2 should the implement be hurled'forward under high ac" celeration or deceleration of a vehicle. There is thus no danger-of ink escaping from the open vent 3i. Yet bore ll despite its small diameter maintains a permanent vent of the ink column and thus precludes blocking of flow by vacuum.

The'helical cavity alfords a supply of ink sufficient to last for some months. When the ink has been used up, if the implement is still service-.- able, itwill have to be sent back to the factory or to a service station for refilling.

Asmany changes couldbemadein the above construction, and many apparently widely (hfferent embodiments of this invention could be made without departing'from the scope of, the claims, it. is intended that all matter contained in the above description, orshownin the acccmpanying drawings, shall be interpreted as illustrative and notin a limiting sense.

Having thus described my invention, .what I claimas new and desire to secure byLettersPatent :of the United States is:

l. A writing implement, comprising a barrel having a cylindrical bore with a conical tapered writing 0nd,:a core having a conical end seated Jinthe corresponding-end of the barrel, aid-axially bored tip threaded into the reduced end of coreand abutting the tip end of said barrel, thereby retaining the conical end of saidcore tightly sealed in the-conical end of said bar eland plugging the latter, .a ball writing point in the forward'end of said tip, said tip having a lip-serving :as a seat for said ball, a helical groove about said core terminating before the forward end of said core and defining with'the inner wall of said bar- 'relacapillary passageway, said barrel having-a rent communicating with the upper endof said passageway, and a transverse bore in said core near the lower end of said passageway communicating with the axial bore of said tip.

2. A writing implement, comprising a barrel having a cylindrical bore with a conical tapered writing end, a core having a conical end seated in the corresponding end of the barrel, said core having a helical groove thereabout, said helical groove extending about themaior pOItion of the length of the core and thence along the conical tip of the core, said groove terminating before the forward end of said core and having a substantially uniform root diameter, the upper end of said core being of continuous cylindrical form and snugly fitted into said barrel, said core having an axial bore in its upper end and an axial bore of smaller diameter in its conical end, an axially bored tip threaded into said latter bore and abutting the tip end of the barrel, thereby retaining the conical end of said core tightly sealed in the conical end of said barrelbelow theend ofgsaid groove ndpl e ng said barr l, a ballzw tins point in the forward'endofsaid-tip, said tip hays ing a lip serving as a seat for saidball, and a pair of .radal bores in said core communicating from the respective axialybores to the helical groove therein, said barrel havlnga vent at the upper part .thereof.

58. A writing implement comprising a barrel having ascylindrical bore with a conical tapered writngend, a core conformed to-thebore of said barreland having a conical forward end fitting snugly in said tapered writing end of the barrel, said core having :a helical ink accommodating groove thereab'out terminating at a substantial distance before the forward endof said cor-e, said groove coacting with the inner wall of said barrel to-form a capillary passageway, part of the length of said passageway being chargedwithpastyink, a tip having an axial bore and secured in an axial borethrough the forward end of =said core and protruding from the-barrel, said tip having ashoulder abuttingthe forward end of-sa'idbarrel and thereby firmlysealing the conical end'of said coreinand against the conical forwardend of'the 'barre1 't0'p1l1g the latter, an axial here into the rear I end ;of the core, transverse bores in said'core extendingfromthe inner part of said 'helical 'groove tosaid bores in thefOrWard part ofthecore' and 'the rear end of the-core-respectively, a vent at the upper end of saidbarrel leading intothe axial bore at the rear end; of-said core :and a small port constituting the sole communication between the capillarypassageway and the vent, said port-being restricted and ofarea much smaller than said vent and serving as an air cushion or dashpot to prevent surging ofith'e ink forward under high acceleration or deceleration of a vehicle. 7

ISIDORCHESLEB.

IREFERENCES CITED The following references are record :in the file'of this patent: 

